The present invention relates to an optical fiber coupler, and more particularly to an optical fiber star amplifier coupler and the fabricating method thereof.
Generally, there are three types of conventional optical fiber networks, i.e., duplex network, T-shaped network and star network, each of which possesses some advantages and shortcomings and is specifically suitable for a certain condition. When many distributed terminals should be linked together for communicating with one another, a possive star coupler of the star network with N input ports and N output ports is widely used to evenly distribute the input signal from each input port to every output ports.
However, as the number of output ports of the star coupler increases, the signal intensity will decrease very fast in accordance with the spliting ratio. This effect limits the maximum number of ports a star coupler can support. For example, current LAN Ethernet system using multimode fiber star coupler can only support less than 33 terminals. An active star coupler is developed to eliminate the shortcomings of the passive star coupler. Such active star coupler functions as the passive star coupler and a relay. It converts received optical signals into electric signals and amplifies the electric signals. The amplified electric signals then energize a light source to produce new high intensity of optical signals which are then evenly distributed to every output ports. However, the amplifying operation of the active star coupler is complicated and the volume thereof is larger with more electronic components contained therein. As a consequence, the manufacturing cost and failure possibility increase. Therefore, such active star coupler appears still unsatisfactory.